Metamath Proof Explorer


Theorem vnex

Description: The universal class does not exist as a set. (Contributed by NM, 4-Jul-2005) (Proof shortened by BJ, 25-Apr-2026)

Ref Expression
Assertion vnex ¬ x x = V

Proof

Step Hyp Ref Expression
1 vneqv ¬ x = V
2 1 nex ¬ x x = V